In reply to:

One of the great attractions of carousels was their mechanical steam organ

If you knew of a carousel or merry-go-round with a steam organ, it would have been most unusual.
A steam organ is called a calliope, usually used by circuses and occupying its own wagon. It would lnot have been used for a carousel because of the danger of explosion with a lot of children close by. What was used for a carousel was a mechanical pneumatic organ, an instrument with a very distinguised pedigree -- Mozart composed at least one piece for mechanical organ.